﻿BUDS 
  AND 
  BRANCHES 
  

  

  101 
  

  

  94. 
  Structure 
  of 
  winter 
  buds. 
  The 
  scaly 
  buds 
  of 
  our 
  com- 
  

   mon 
  trees 
  and 
  shrubs 
  are 
  readily 
  picked 
  to 
  pieces 
  as 
  soon 
  

   as 
  they 
  begin 
  to 
  swell 
  in 
  early 
  spring, 
  but 
  it 
  is 
  easier 
  to 
  dis- 
  

   tinguish 
  the 
  parts 
  of 
  which 
  they 
  are 
  composed 
  by 
  watching 
  

   the 
  opening 
  process 
  from 
  the 
  very 
  beginning. 
  Sections 
  of 
  

   buds, 
  if 
  carefully 
  made, 
  show 
  very 
  clearly 
  the 
  relations 
  of 
  the 
  

   parts 
  (fig. 
  85). 
  In 
  a 
  leaf 
  bud 
  there 
  are, 
  on 
  the 
  outside, 
  the 
  

   leathery 
  bud 
  scales 
  ; 
  inside 
  of 
  these 
  are 
  rudimentary 
  leaves 
  ; 
  

  

  FIG. 
  87. 
  Cottouwuod 
  twigs, 
  April 
  15 
  

  

  The 
  flower 
  buds 
  on 
  the 
  lower 
  twig 
  (developing 
  into 
  catkins) 
  are 
  fully 
  open, 
  but 
  

   the 
  leaf 
  buds 
  are 
  still 
  closed. 
  Reduced 
  

  

  and 
  within 
  and 
  below 
  the 
  leaves 
  is 
  a 
  central 
  axis 
  tipped 
  with 
  

   a 
  growing 
  point 
  composed 
  of 
  rudimentary 
  cells 
  capable 
  of 
  rapid 
  

   division 
  and 
  growth. 
  

  

  The 
  scales 
  which 
  cover 
  buds 
  are 
  often 
  the 
  dwarfed 
  and 
  

   otherwise 
  modified 
  leaves 
  or 
  leafstalks, 
  as 
  is 
  well 
  shown 
  in 
  

   some 
  buckeyes 
  and 
  in 
  roses 
  in 
  which 
  the 
  opening 
  buds 
  present 
  

   a 
  series 
  of 
  gradations 
  between 
  mere 
  scales 
  and 
  foliage 
  leaves 
  

   (fig. 
  76). 
  In 
  other 
  cases, 
  as 
  in 
  oaks, 
  beeches, 
  lindens, 
  and 
  

   magnolias, 
  the 
  scales 
  represent 
  the 
  appendages 
  (stipules) 
  found 
  

   at 
  the 
  bases 
  of 
  many 
  leaves. 
  Frequently 
  bud 
  scales 
  are 
  cov- 
  

   ered 
  with 
  a 
  dense 
  layer 
  of 
  hairs 
  or 
  down, 
  and 
  sometimes, 
  as 
  in 
  

  

  